1. Field of the Invention
The subject invention relates to connectors and connector unions for standard tubes and pipes and, more specifically, to fully integrated self-contained connectors and unions with various built-in safety features.
2. Information Disclosure Statement
The following disclosure statement is made pursuant to the duty of disclosure imposed by law and formulated in 37 CFR 1.56(a). No representation is hereby made that information thus disclosed in fact constitutes prior art, inasmuch as 37 CFR 1.56(a) relies on a materiality concept which depends on uncertain and inevitably subjective elements of substantial likelihood and reasonableness and inasmuch as a growing attitude appears to require citation of material which might lead to a discovery of pertinent material though not necessarily being of itself pertinent. Also, the following comments contain conclusions and observations which have only been drawn or become apparent after conception of the subject invention or which contrast the subject invention or its merits against the background of developments which may be subsequent in time or priority.
Except for the familiar threaded or glued tube and pipe connectors, most types of fluid conduit, pipe or hose connectors appear to require the presence of interfitting male and female members, as may be seen from U.S. Pat. Nos. 4,063,760, by L. Moreiras, issued Dec. 20, 1977, 3,922,011, by T. Walters, issued Nov. 25, 1975, 3,635,501, by T. Thorne-Thomsen, issued Jan. 18, 1972, 3,439,943, by T. Thorne-Thomsen, issed Apr. 22, 1969, 3,352,576, by T. Thorne-Thomsen, issued Nov. 14, 1967, 3,468,562, by Ho Chow et al, issued Sept. 23, 1969, 3,428,340, by H. L. Pelton, issued Feb. 18, 1969, 3,120,968, by J. H. Calvin, issued Feb. 11, 1964, 2,939,728, by J. A. Bitel, issued June 7, 1960, 2,914,344, by C. C. Anthes, issued Nov. 24, 1959, 2,631,872, by F. T. wurmser, issued Mar. 17, 1953, 2,579,314, by V. J. Grumblatt, issued Dec. 18, 1951, 2,521,701, by C. E. Earle et al, issued Sept. 12, 1950, and 1,587,079, by S. Machino, issued June 1, 1926, British Pat. No. 671,480, by R. Creelman, published May 7, 1952, and Soviet Pat No. 576,481, by V. V. Abramov et al, issued Oct. 15, 1977, for instance.
In practice, this requires rather special tooling, machining or expensive manufacturing steps in providing the interfitting male and female coupling members. For instance, there is no practically feasible way of making the wire loop cage of the female member of the above mentioned Walters U.S. Pat. No. 3,922,011 by machining.
Moreover, interfitting male and female members rather typically make for a stiff coupling joint, so that there is no significant flexibility which would tolerate lateral angular movements of the interconnected pipes.
Furthermore, the above mentioned references include couplings in which a threaded nut has to be removed in order to effect disconnection of an inserted male member, as may be seen from the above mentioned U.S. Pat. Nos. 4,063,760, by L. Moreiras, and 2,579,314, by V. J. Grumblatt, and British Pat. No. 671,480, by R. Creelman, for instance. In fact, the above mentioned U.S. Pat. No. 4,063,760, by L. Moreiras, proposes a second embodiment that does not require removal of a threaded nut. However, the coupling according to that further embodiment has to be destroyed if disconnection thereof is desired.
Many of those proposed couplings also require forceful insertion of the male member against the bias of a locking spring, and frequently need to accommodate the locking spring in an annular groove in which the locking spring comes to sit loosely, after the male member has been fully inserted, as may, for instance, be seen from the above mentioned U.S. Pat. Nos. 4,063,760, by L. Moreiras, 3,120,968, by J. H. Calvin, and 2,939,728, by J. A. Bitel, British Pat. No. 671,480, by R. Creelman, and Soviet Pat. No. 576,481, by V. V. Abramoy et al.
If garter springs are employed for that purpose, then a design results in which the locking spring is easily pulled out of the fixture, such as in the case of the above mentioned U.S. Pat. No. 2,914,344, by C. C. Anthes. The latter and other proposals mentioned above do not even provide a self-locking action, so that it is readily possible that the connection will blow open under pressure.
Moreover, many of these proposals require the provision and housing of a helical or other lateral spring, which makes for a longer coupling design, as may be seen from the above mentioned U.S. Pat. Nos. 3,439,943, by T. Thorne-Thomsen, 3,352,576, by T. Thorne-Thomsen, 3,468,562, by Ho Chow et al, 3,120,968, by J. H. Calvin, 2,631,872, by E. T. Wurmser, 2,521,701, by C. E. Earle et al, and 1,587,079, by S. Machino.
The number of engagement points is inherently limited in these and other references, such as the above mentioned U.S. Pat. Nos. 3,428,340, by H. L. Pelton, 3,352,576, by T. Thorne-Thomsen, 2,521,701, by C. E. Earle et al, and 1,587,079, by S. Machino, and the Soviet Pat. No. 576,481, which renders the achievable tightness of the fluid coupling unde high pressure questionable.
References which provide a kind of valving in the joint members introduce a severe restriction of the fluid flow passage and sharply reduce throughput, as may, for instance, be seen from the above mentioned U.S. Pat. No. 3,120,968, by J. H. Calvin, and from U.S. Pat. No. 4,362,326, by E. F'Geppert, issued Dec. 7, 1982. The latter proposal also requires loose locking wires and an annular locking mechanism to encompass the outside of the interlocking tubes themselves.
Against this background, the tubing coupling with electrical bonding according to U.S. Pat. No. 3,999,825, by Clifford D. Cannon, issued Dec. 28, 1976, to a subsidiary of the subject assignee, has the great advantage of permitting a flexible interconnection of standard tubing. Only lack of skill of the operator could effectively impair that coupling which, in practice, could, however, be a serious factor with careless personnel that fail to apply themselves to the task at hand.
As its name implies, the subsea wellhead connectors according to U.S. Pat. No. 4,496,172, by J. M. Walker, are more suitable for hydraulic connect and disconnect at a submarine or other remote location.